Silverlight data in matrix

Does anyone know how to arrange some data to a data matrix? A simple example:

For example the model would be the following:

public class SampleItem 
{
    public string Category { get; set; }
    public int DayOfMonth { get; set; }
    public double Value { get; set; }
}

I would like to have a List<Samp开发者_JS百科leItem> displayed in data matrix something like

DayOfMonth | 1 | 2 | 3 | 4 | ...
---------------------------- ...
Category1  |   | 7 |   |   | ...
Category2  | 2 |   | 5 |   | ...
Category3  | 1 | 6 | 5 | 1 | ...

So in the intersection of rows and columns it would display sum of Value where DayOfMonth = Column name and Category = row name.

Is it possible to have this? Maybe with non-static rows for categories and by any chance in a datagrid to enable grouping?

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Since DataSet is not available within Silverlight you could use this DataSet perhaps just the DataSet type within that framework as it is geared towards something else. Once you have a table like structure you could simply walk the data or poll the data and define your sums as needed.